Genetically pure bison planted on prairie

The planned release Wednesday of 16 bison on the north-central
Montana prairie marks the start of bringing back the plains bison
from ecological extinction.

While the burly beasts look like your average bison, they're
not. The animals are among the few remaining genetically pure bison
in North America.

The private wildlife preserve project by the World Wildlife Fund
and the American Prairie Foundation is to establish a wild herd of
genetically pure bison that eventually will be large enough to
reclaim its key role in Montana's prairie ecosystem.

That means having large herds of bison roaming over the
landscape, which for now is 31,000 acres of land purchased or
leased by the American Prairie Foundation.

"We have some unique bison genomes and we need to act to make
sure they're conserved," said Curt Freese, Northern Great Plains
Program director for the World Wildlife Fund.

The Montana project began about four years ago, after a search
for a grassland ecosystem that could support a bison herd and other
plant and animal species led the conservationists to north-central
Montana.

There, the World Wildlife Fund found a patchwork of public and
private lands neighboring the C.M. Russell National Wildlife Refuge
and teeming with native plants and animals on a mostly pristine
prairie.

Although there are about 500,000 plains bison in North America,
only about 5,000 of the animals are considered genetically pure and
they face ecological extinction, the groups said. The rest of the
bison have cattle DNA as a result of cross breeding.

Ecological extinction, Freese said, refers to the species' role
in the environment. Historically, plains bison roamed over large
landscapes, grazed with varying intensity, created mini-wetlands
and wallows and provided carcasses to scavengers and nutrients for
plants.

He points to the decline in populations of grassland bird
species, which is falling faster than any other group of bird
species, as a consequence of prairies without bison. A possible
reason for the decline in bird species is that bison, through their
grazing patterns, no longer create the habitat to which grassland
birds became adapted, he said.

"To recreate the ecological effects, we're going to have to
learn as we go," Freese said.

Once released, the bison herd will be monitored and tracked
through radio collars and satellite global positioning systems to
see how they use the range and affect other wildlife, Freese
said.

The information will be shared with ranch neighbors, along with
the U.S. Fish and Wildlife Service and the Bureau of Land
Management, which manage public lands nearby.

Genetic purity and diversity is another important goal of the
project.

The bison being released came from South Dakota's Wind Cave
National Park, which has about 400 genetically pure bison on about
10,000 acres.

Four or five other herds in North America also have shown
through research testing to be pure. The majority of pure bison are
in the Yellowstone National Park herd, Freese said.

The conservation groups would have considered relocating some
Yellowstone National Park bison to their north-central Montana
preserve if the animals were free of the disease brucellosis, but
they're not, Freese said. The disease can cause cattle to
abort.